I am looking at the Avanti website at the tickets for 15/09 and they allow you to book the "LTS RAIL LTD" operated trains either at standard or first class prices. Which is odd given the whole train is first class seating only?
I did a search on Realtime Trains for Euston on Friday and I got:
1159 arrival from Manchester Pic: Std only, reservations not available
1233 dep to Manchester Pic: First and Standard, "restaurant for first class passengers" (which just means at seat service I think), reservations compulsory
1553 arrival from Crewe: doesn't mention classes or reservations
1742 departure to Manchester Pic: doesn't mention classes or reservations
1858 arrival from Manchester Pic: Std only, reservations not available
1923 dep to Manchester Pic: First and Standard, "restaurant for first class passengers" (which just means at seat service I think), reservations compulsory
Given the platform numbers it strikes me that they've mucked it up. I did wonder if they had one set with both, but I given the platforms it seems fairly obvious that the ones that form the other ones aren't the same, i.e. the 1858 arrival is P16 as is the 1923 departure, which means it'll be the same set.
Edit: I just tried a dummy booking and it was walk up fares only and counted places, no actual seat reservations.